The surveillance system for invasive bacterial diseases, active in our country, recorded 1,462 cases of invasive disease caused by Streptococcus pneumoniae in 2016, equal to almost 80% of all notified cases. “The risk of developing invasive pneumococcal disease in adults is influenced by various factors, including age, the presence of comorbidities (e.g., heart disease, diabetes, chronic lung disease), immunocompetence status, and exposure to children infants. Children under one year of age, adults over age 65, and those with underlying health conditions are at significantly increased risk of invasive disease. Precise quantification of risk may vary based on the population studied and to the geographic context, but studies have shown that the incidence of invasive disease can be several times higher in very young children and adults with specific risk factors compared to the general adult population.” This was stated by Caterina Rizzo, full professor of General and Applied Hygiene, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, speaking this morning at a media tutorial in which the positive results of numerous studies were discussed. phase 3 which evaluated V116, the first 21-valent pneumococcal conjugate vaccine in development, specifically designed to protect adults and which should be approved in June this year by the American FDA.
“The prevalence and distribution of the main pneumococcal serotypes in the Italian adult population – continues Rizzo – are reflected in the trends observed following the introduction of conjugate vaccines against Streptococcus pneumoniae. The introduction of the 7-valent conjugate (Pcv7) and subsequently of the 13-valent conjugate vaccine (Pcv13) has “changed the epidemiology and” led to a significant reduction in cases of invasive pneumococcal disease (Ipd) in children and, due to herd immunity, also in the adult population. However, This decrease has been accompanied by the emergence of 'replacement strains' not included in vaccines, indicating a change in the distribution of serotypes responsible for invasive infections.”
“The introduction of conjugated vaccines in pediatric age – continues Rizzo – has led to the appearance of different serotypes in the elderly population”. V116 was “developed from the serotypes that, in adulthood, most frequently cause pneumococcal disease, therefore based on epidemiological evidence”. Contrary to what was expected, “i.e. a reduction in the immune response for some serotypes, due to interferences that develop when many are added”, the 21-valent “has developed effective immunological responses – he concludes – for all serotypes”.
